For proper tests use 100 percent fuel, and you use a fuel burn of 1.0 (offline not in the MA where it is set to 2x fuel burn rate) at ALT (@18-22k) and reduced throttle to standard CRUISE settings. Also, dont "count sectors"??? you hit the "ESC" key once airborne and then hit the "E6B" button on the panel (third one down) and it reads off the current range. Thats how you do a proper test.
Ranges for the following a/c on INTERNAL fuel only (no Drop Tanks) at 100 percent internal capacity, at cruise settings in Real Life is this:
Ki-84: 1053 miles
F4U-1D: 1015 miles
P-51D: 950 miles
P-38J: 890 miles
> Me-262: 652 miles <
P-47D-1: 570 miles
Fw 190D-9: 519 miles
Me 109G-6: 465 miles
Spitfire IX: 434 miles
The Ki-84 and F4Us ranges are max ranges at much reduced throttle, not typical combat ranges.
As you can see the Me 262s range is actually greater than many of the single seat fighters on internal fuel. 652 miles puts it into the top 1/2 category. Its range vs the Spitfire IX on internal fuel is @ 50 percent greater, no doubt owing to its much higher cruising speeds on jet engines once at alt.
Stop using 25 percent fuel and flying at 500 feet at max power in the Main Arena when you test them. It will not give an accurate result.
Also keep in mind that ranges vary greatly depending on alt, throttle, WEP use, ect and that they are only "generalised #s" they are never absolutes.